Say or Said/ insist or insisted

A. Say or Said?

When I met Peter, I say ' What are you doing?'

B. insist or insisted?

I insist that I am right.
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say 系Present tense ge 時候用
甘Said 就系DIrect Speech ge 時候用

在英文的文化裏，有一條規則叫時式一致(Sequence of Tenses)：所以，在Ａ題裏，我們留意到met是過去動作，所以同樣say也必須是過去式，所以要用”said”

而Ｂ題，從屬子句的動詞是am，所以主要子句的動詞就不可以是過去式，所以是答案是：insist

A.
When I met Peter, I said "what are you doing?"

B
I insist that I am right. <---------------如果現在仲係
I insisted that I am right. <------------------以前係....但而家唔係..........

say.......很少機會會用到.....要用的話.....就use as present tense....
said......多數係用在direct speech and indirect speech.....
eg. Peter said, "I am stupid."
Peter said that he was stupid.

present condition.......
睇下講緊的事情.......
係幾時發生.......
時間唔同.......
就用唔同的tense........