“庄稼一支花，全靠肥当家”。合理使用化肥，才有利于农作物的生长和减少环境污染。下列有关化肥的说法正确的是(   )

下面关于食物链的表示中哪项是正确的（　　）

A: Hey, Tim. Is he y____  pen pal?
B: Yes. He is a cute boy.
A: W ____   his name?
B: Peter.
A: Where is he f____?
B: The United Kingdom.
A: W____ does he live ? Does he l  ____   in London?
B: Yes, he does.
A: What l  ____  does he speak?
B: English a   ____    Chinese.
A: C  ____ he speak Chinese well?
B: No. He can only speak a l  ____   Chinese.
A: Do you often get his e-mails?
B: Yeah. He w  ____   to me every week.

①学习只有痛苦没有快乐,不如放弃

②要学会自主学习,提高学习效率

③人有学习的天性，学习与生命发展同步

④学习虽然是辛苦的,但成功以后可以得到一种超越自我的快乐