This isn’t Chinglish, just bad teaching methodology. Unfortunately, native Taiwanese English teachers here often have several reasons they teach the class primarily in Chinese. Below are some of the most common ones.
[ol][li]That’s how they were taught and they don’t know of any other way.[/li]
[li]The children don’t understand when they explain in English, so they teach in Chinese so the children understand.[/li]
[li]They are using a grammar-translation model. Explanation of grammar is done in the native language, then students go through drills (mostly written) transforming conjugations and learning the grammar, as well as many translation drills.[/li]
[li]The local teachers are not confident in their own English ability. They fear making an error, so they avoid speaking English except for the specific material they are modeling.[/li][/ol]None of these are a valid reason to teach that way. Grammar-translation as an exclusive method has been shown to be less effective in teaching a majority of students. More modern approaches would be more effective. The other reasons are just excuses.
Are you being brought in to observe so you can give feedback, or so that you can see what the kids are learning? If you are being asked to give feedback it is important how you go about giving it. If you are not being asked to give feedback, it is even more important how you go about giving it.
If you are in the blessed position of being asked for your advice, try to let them come to the same conclusions as you with some tactful questions. Something along the lines of:
[quote=“Perhaps you could have said or”]How much English do you think you are speaking in class?
How much English do you think the students are speaking in class?
Do you think it’s important for students to hear and speak English in your English class?
Do you think you can explain English grammar through example using only English so that students can understand?[/quote]
If they follow your reasoning and conclusions, you could then offer to demonstrate some techniques. If they don’t… well, it really depends on your own background and qualifications to decide what comes next.
If you are not in the blessed position of being asked for your advice, you’ll have to sound them out to see if they will be willing to listen to your advice. Perhaps ask them how their class is going, what they think is the biggest challenge with their class, etc. There’s a very good chance they won’t be even remotely interested in hearing your opinion and any attempt to tell them how to do their job will be viewed as arrogant and unwelcome.
That will be 2 cents, please.