连词主要有：when as while before after until as soon as since等
(1)区别when, as, while的用法
_________ the students heard the teacher's footsteps, they all stopped talking.
We were having breakfast __________ she was combing her hair.
I can learn ________ I work.
用when, as, while填空：
________ you came in, I was talking with a few boys.
It started to rain __________ we were playing outdoors.
They talked _________ they walked down the river.
__________ it was raining, the students were playing basketball.
Her brother watched TV__________ he ate supper.
I'll be back _______________________________________________.
(5) as soon as暗示"一……就"，做题要留意主将从现
As soon as we __________ (get) there, he ___________ (tell) us the news.
We __________ never __________ (meet) since we ___________ (graduate) from the college.
(8) till/until引导的时间状语从句 till和until同义，作"直到……时(为止)"解，till多用于非正式文体，until多用于句首;not … until凡是与after举办转换。如：
I won't go with you until(till) I finished my homework.