如：He said that the sun is bigger than the earth.
.如果賓語從句所表示的是客觀事實、普遍真理、自然現象等，不管主句用什麼時態，從句時態都用一般現在時。
1)The teacher said that the earth turns the sun.老師說地球繞著太陽轉。
2) He told me that the earth is round.
3) He said that the light travelsmuch faster than sound.
1. 當賓語從句是指客觀事實、普遍真理、自然現象時，主句不管是什麼時態，從句只能用一般現在時。
如:
She said （that） the sun rises in the east.
She told me （that） knowledge is power她告訴我知識就是力量。
2. 當主句是：Could you help; \ Would you help;表示建議或者請求的句型時，主句的時態是一般現在時，從句時態不限定。
如: Would you tell me what you want to eat ?
Could you tell me how he will come tomorrow你能告訴我他明天怎麼來嗎?
3. 當疑問代詞在賓語從句中作主語，從句語序不需要改變，
如:what's the problem/ what's the matter/ what's up/ what's wrong表示 "怎麼了" .
I don't know what's the problem/ what's the matter/ what's up/ what's wrong我不知道出了什麼問題。
如：He said that the sun is bigger than the earth.
.如果賓語從句所表示的是客觀事實、普遍真理、自然現象等，不管主句用什麼時態，從句時態都用一般現在時。
1)The teacher said that the earth turns the sun.老師說地球繞著太陽轉。
2) He told me that the earth is round.
3) He said that the light travelsmuch faster than sound.
1. 當賓語從句是指客觀事實、普遍真理、自然現象時，主句不管是什麼時態，從句只能用一般現在時。
如:
She said （that） the sun rises in the east.
She told me （that） knowledge is power她告訴我知識就是力量。
2. 當主句是：Could you help; \ Would you help;表示建議或者請求的句型時，主句的時態是一般現在時，從句時態不限定。
如: Would you tell me what you want to eat ?
Could you tell me how he will come tomorrow你能告訴我他明天怎麼來嗎?
3. 當疑問代詞在賓語從句中作主語，從句語序不需要改變，
如:what's the problem/ what's the matter/ what's up/ what's wrong表示 "怎麼了" .
I don't know what's the problem/ what's the matter/ what's up/ what's wrong我不知道出了什麼問題。