Đây là một trong số những bài giảng tiếng Anh cơ bản thuộc tập các tài liệu tiếng Anh được biên soạn dựa trên các tài liệu trên mạng Internet. Các phần trong bài giảng được chú giải hoặc dịch ra tiếng Việt.
Time Clauses Using Before, After, While and When The Grammar Independent clause Dependent clause The phone rang before we ate dinner The phone rang is an independent clause It can stand alone grammatically before we ate dinner is a dependent clause It needs an independent clause to be a complete sentence It is a sentence fragment when it is used alone Punctuation The phone rang before we ate dinner Before we ate dinner, the phone rang When the independent clause comes first in the sentence, no comma is needed When the dependent clause comes first in the sentence, the clauses are separated by a comma Different verb tenses Look at these verb tenses: two past tense It started to rain before I got home events Jaime had a drink before he played tennis modal I have to get home before it starts of rain auxiliary and present tense Jaime has to have a drink before he plays tennis two past tense Henry went to the movie after he had dinner events Prof Simon gave a test after the spring break ended modal Henry may go to the movie after he has dinner auxiliary and present tense Secretary Simon ought to negotiate with the rebels Nguyen Trung Kien – BoE/BoFEs Center for Languages for Specific Purposes and Translation College of Foreign Languages – V.N.U, Hanoi 2006 Time Clauses Using Before, After, While and When before the situation gets out of hand an on-going event Myra was reading a book when the phone rang interrupted by a single event in the past past tense cause Myra had to get up when the phone rang and effect two past tense Ben asked for a ride when Myra answered the events phone two future events Myra will leave to pick up Ben when she hangs up two past tense I was listening carefully while the manager was continuous explaining the problem activities one past tense continuous event The doorbell rang while I was taking a shower interrupted by single action Cause and Effect You can use when or after to explain some cause and effect situations Effect: He got a flat tire (puncture) Cause: He ran over some glass He got a flat tire after he ran over some glass After he ran over some glass, he got a flat tire Cause: It rained Effect: Our paint job was ruined When it rained, our paint job was ruined Our paint job was ruined when it rained Nguyen Trung Kien – BoE/BoFEs Center for Languages for Specific Purposes and Translation College of Foreign Languages – V.N.U, Hanoi 2006