哪些是真正不锈钢管:解释一下complain的词性

they do complain 中的 do 可以理解为“确实”这种加强语气的词，是助动词

complain: [ kəm'plein ]

v. 抱怨,悲叹,控诉

例句与用法:
1. They complained bitterly about the injustice of the system.
他们愤恨地抱怨制度不公平。

2. The tourist complained that the room was too dirty.
游客抱怨说房间太脏了。

3. He is always complaining.
他总是在发牢骚。

4. You're always complaining!
你总是发牢骚!

5. The patient is complaining of acute earache.
病人说耳部剧痛.

6. Don't complain without good cause.
没有充分的理由就不要抱怨。

7. You've got nothing to complain about.
你没什么可抱怨的。

8. Stop grumbling! You've got nothing to complain about.
别抱怨了! 你没什麽可抱怨的.

英英解释:
动词complain:

1. express complaints, discontent, displeasure, or unhappiness
同义词：kick, plain, sound off, quetch, kvetch

2. make a formal accusation; bring a formal charge

他经常抱怨

vi.
抱怨；埋怨；申诉；控诉；控告
They complained about the food.
他们抱怨这糟糕的食物。
Almost immediately he began to complain about the weather.
他几乎马上就开始抱怨起天气来了。
Jean is always complaining

既能做及物动词也能做不及物动词