英文文法有問題?

I am sick -- present tense = 我正在生病
You use present tense to convey that for now, at present, you are in a state or doing something.

I was sick -- past participle tense
You use past participle tense when you recall past events, for example, yesterday you went into a restaurant with a friend for dinner; she was really happy to see you.

The past participle verb of I/he/she/it(singular) is was.
The past participle verb of I/you/they/we(you and plural) is were.

Hope it helps :)

請解釋什么是 "past participle tense"

i am sick=我e+病,一般係口語,同朋友講.或者講歷史,令人有置人其中嘅感覺.但呢個係美式用文,你考試唔會用到,可以唔理.
i was sick=我嗰時病,一般係寫故事,講之前嘅事.
同埋文法通常跟前文後理,如果一路講故仔,用緊過去式,照跟.但如果係"",講嘅嘢,有可能會變,但意思完全一樣.
sick=想嘔嘅病,例如腸胃病,所以憎1個人,作嘔=get sick of,其他病係ill