Text to Speech for EFL ESL Materials

Text to Speech (TTS) technology has come a long way in recent years and this is nowhere more evident than on the Read The Words website.

I've just been having a look at the site and trying to decide whether it has real potential for helping EFL ESL students with their listening, reading and pronunciation.


As an experiment I decided to select quite a challenging text and see what the site could do. I also decide to select a British English accent, as in the past I know that TTS systems had struggled more with UK accents than US ones, due to the wider range of sounds in UK English.

Anyway, here are the results. The text is from Wikipedia.org at: http://en.wikipedia.org/wiki/Text_to_speech and is about the challenges of text normalisation in TTS.

• Click here to watch Elizabeth read the text to you.
  Or
  

• Listen using this media player

This is the actual text you should be hearing:

"Text normalization challenges

The process of normalizing text is rarely straightforward. Texts are full of heteronyms, numbers, and abbreviations that all require expansion into a phonetic representation. There are many spellings in English which are pronounced differently based on context. For example, "My latest project is to learn how to better project my voice" contains two pronunciations of "project".

Most text-to-speech (TTS) systems do not generate semantic representations of their input texts, as processes for doing so are not reliable, well understood, or computationally effective. As a result, various heuristic techniques are used to guess the proper way to disambiguate homographs, like examining neighboring words and using statistics about frequency of occurrence.

Deciding how to convert numbers is another problem that TTS systems have to address. It is a simple programming challenge to convert a number into words, like "1325" becoming "one thousand three hundred twenty-five." However, numbers occur in many different contexts; when a year or perhaps a part of an address, "1325" should likely be read as "thirteen twenty-five", or, when part of a social security number, as "one three two five". A TTS system can often infer how to expand a number based on surrounding words, numbers, and punctuation, and sometimes the system provides a way to specify the context if it is ambiguous.

Similarly, abbreviations can be ambiguous. For example, the abbreviation "in" for "inches" must be differentiated from the word "in", and the address "12 St John St." uses the same abbreviation for both "Saint" and "Street". TTS systems with intelligent front ends can make educated guesses about ambiguous abbreviations, while others provide the same result in all cases, resulting in nonsensical (and sometimes comical) outputs. "

What I like about the site

• The site is free though you do have to register.
• The site creates a number of options once it has converted the text to speech. This includes creating an Mp3 file to download, creating an embed code to embed the audio into a blog or website, or download to i-pod.
• They have quite a selection of avatars and voices
• The site can convert text from a number of sources including Word, PDF, a website (just type in the URL) or even an RSS feed!
• You can make the texts private or public
• There doesn't seem to be a limit on many you can create
  

What I wasn't so sure about

• I found it hard to get a link to the avatar reading the text. It would have been nice to be able to embed her into my blog, but I just couldn't get that to work.
• Processing the text can take a while.
  

I haven't added any teaching suggestions yet for this posting, as I'm interested to see what other teachers think about this before I do that.

So, if you've listened to the text, please do send in a comment and let me know what you think about the useability of a tool like this with EFL ESL students.

Related lnks:

• Dictation goes Web 2.0
• Artificial Intelligence Chat bots and EFL ESL

Activities for students:

• Listen and Write the News
• Listen to and Download Texts

Best

Nik Peachey

Pronunciation goes 2.0

I've been looking this week at Forvo, which is a kind of web 2.0 pronunciation site. The site allows users to request, and add audio clips of the pronunciation of different words from a huge range of languages, so if you want to know how a word is pronounced you can either do a quick easy search for the word and then listen to it, or if the word isn't already within the database, you can add it and request a pronunciation.

The site also categorises words into lexical areas such as brands, acronyms, sports etc which is very handy

You can also be helpful and add the pronunciation to words which have been requested in your language.

The site offer free registration, but you can find words, request words and pronounce words without registering. The benefit of registration is that you'll be notified when someone pronounces your word for you.

What I like about it

• It's a great idea and it's free
• Very easy to use interface
• Lots of different languages
• Sound clips load quickly and a reasonably good quality
• Registration isn't required
• Potentially a huge and growing resource

What I'm not so sure about

• Like most things on the web, especially Web 2.0, you can't be sure of the quality or authenticity of what you are getting, so if you are using this with students check out the words they are after and make sure the quality of the pronunciation is good (My litmus test was 'aluminium' and it feel somewhere between the UK and US versions)
• Watch out for students who want to pronounce the (four letter) words that they shouldn't be using (though probably better for them to pronounce them well than badly)
• It would be really nice to have regional variations of the pronunciation, but I guess that's broadening out the amount of work a bit far.
  

How to use this with students

• This is a nice self access resource for students to check their pronunciation
• You could give students a list of words and get them to find out how they are pronounced
• Get students to add some words that they want to be able to pronounce
• Use the site to dictate words while students listen, then get them to go to the site and check that they have got the right words
  

This is a really nice application of the Web 2.0 concept to pronunciation and it will be really interesting to see how this site grows and develops.

Hope you enjoy it and can get your students involved.

Best

Nik

Phonology can be fun and free

Phonetics Focus is a really wonderful new free resource produced by Cambridge English Online Ltd.

Basically it is a collection of interactive multimedia Flash based games and resources that can be accessed through the CEO website at http://cambridgeenglishonline.com/Phonetics_Focus/

What is it?
In all there are almost 20 different interactive tools all accessible through the one page. These vary from an interactive phonemic chart where users can click on the symbols to hear the sounds and so develop their knowledge of the chart and the phonemic alphabet, through to more fun games which involve shooting the correct sounds to make a word in a ‘duck shoot’ type game.

What I liked about it
All of the activity types are pretty intuitive as they draw on standards like hangman, odd one out, word searches etc and they all have clear instructions. Many of the games and quizzes also have more than one level so this isn’t just for beginners.

Some of the really exceptional features are:

• ‘Record and Practice’ which is a small tool that users can download to help them record and listen back to what they are saying.

• ‘Flashcard Maker’ which helps you to make your own flashcards by either using images from an image library or sketching you own pictures on the program, and adding phonemic symbols to them. You can then print them up for use in class.

• ‘Entry and Exit’ tests so that students can check their level before using the tools and then check again as often as they want afterwards.

What wasn’t so good
I can’t think of anything much wrong with this

Conclusion
I have to say that it’s rare to find really good computer based pronunciation materials, but to find them for free is a real exception. They are really nicely designed, work well, load pretty quickly and have made really good use of multimedia. This is a fantastic free resource that will be useful for teachers and for students of any level or age too.

Be sure to check it out

Please feel free to leave a comment if you use these tools and let me know how it goes.

Best

Nik

Pronunciation videos

This is a useful site if you are teaching pronunciation. Though it could take some time to load the first time you use it.

There is a phonemic chart which has small audio clips of the phonemes along with video clips that show the mouth movements as the sounds are made. (Be warned, this is quite a big file)

Open pronunciation chart

You simply click on the mouth and then watch and listen. I’m not so sure how helpful seeing the mouth is with some of the sounds, but with some it could be quite helpful.

Because the chart is a Flash (swf) file if you right click on it, you can ‘zoom in’ and this makes the view of the mouth much larger. You can even fill the whole screen with just one clip if you want to, though this looks a bit scary!

If you use the menu at the side you can turn off the symbols and just have the video clips, so you could use this for a phonemic dictation activity. (Students listen and write down the phoneme they here)

You could also use it to pronounce words while your student try to spell them out (in standard script)

Also if you click the chart where it says ‘Words’ you will see a word chart and clicking the words that are in blue gives you a page with the different sounds that make up that word.

The page is there to promote the software that the company ‘Thrass’ is selling. I haven’t tried the software, so I don’t know if it is any good. If anyone does try it or buy it could you post a comment to say what you think of it?

Also please post ideas for activities using the free page if you think of any.

Best

Nik