20點*急!!關於英文tense問題><!

1. 係用簡單現在式（simple present tense），即係乜都唔使加，唔使改用現在分詞（即係唔使+ing）。（但係如果係第三身單數就要記住 +s / +es）

2. I go to swin/swimming every Sunday. （every 後面係跟單數名詞嘅，所以係Sunday而唔係Sundays。）

無論前面動詞係乜嘢 tense，後面都可以用 to swim 或者 to swimming，但就一定唔係swam 或 swum。呢度同tense冇關，to swim 係 infinitive，而如果用 to swimming 嘅話，swimming 就係作名詞用。其實呢句句子可以唔使咁累贅，簡簡單單話：I swim every Sunday. 就可以了。

1所有表示經唔經常:always/often/x a week/every x/ seldom/ frequently/ usually/ never/ sometimes 都用現在式,現在進行式/動名詞先加ing,現在式=I /we/you/they+動詞原式,he/she/it就+動詞原式嘅第3身單(多數+s)
2go=現在式,swimming=動名詞,動詞+ing變名詞叫動名詞
例:he/she goes swimming
we/you/they/I go swimming
題外話:傳統every後面要+單數,每個星期日=every Sunday,文法上冇可能+s,你話人,怕everyone,要用he/she,用又煩,唔用又性別歧視,先用they.但Sunday都用it,就唔應該用呢種新式文法

The present,the present time,the time now passing;at present,now;
We don't need any more at present.
for the present,for the time being,as far as the present is concerned;eg.
That will be enough for the present.
Kinds of present tense(be,have,write.)
(1)Primary tenses;Now:I write,
(2)Perfect tenses;Present Perfect:I have written.
(3)Progressive tenses;Present continuous:I am writing.
Present perfect continuous:I have been writing.
Always(adverb) She's nearly always(adv.)at home in the evening.
Once a week(adverb)This clock needs winding once(adv) a week.
:I have read every(adj) book on the shelf.
Every (adj)boy in the class passed the exam.
I have every(adj) reason to believe that (......)
For universial truth every day eg:-
The sun rises in the east every day.
For three eg. on every Sundays:-
I go to swim every(adj) Sundays.
He tries to meet her every(adj)wish every (adj) Sundays.
We enjoy a game of football every(adj) Sundays.
...........(the emphasis being on the unit,not on the total or whole day called Sunday.)

I (go) to (swim) every Sundays.

不是所有句子有 always 或者once a week, every Sunday 要用 Present simple tense. 要看整句子而決定, 特別有其他的clause.

I go to swimming every Sunday. (Habit)

When I lived in England, I went to swimming every Sunday.
(I don’t live in England now.)