您好！請教關於英文文法助動詞問題 我在某個英文書中 文章提到 The first thing she does is take a shower. 中間的 " does is " 連續使用了兩個助動詞，在文法書顯示助動詞不能連用，難道是文章錯了嗎？還是有其他意思呢？

台灣學生一直被此一句法所困擾。有必要特別說明此一句型結構，構成要件
[名詞片語 當主詞包含動詞 do/does/did] + is/was + [(to) V.　不定詞補語］

1.) 名詞片語當主詞， What 子句 或 fused relative clause
2.) 必須含有動詞ｄo/does/did/done，
3.) 這時 is/was 後不定詞補語可省略to (稱為 bare infinitive)

[What I want to do] is (to) sleep.
[What he's done] is (to) spoil the whole thing.
[What John did to his suit] was (to) ruin it.
[What I'm going to do to him] is (to) teach him a lesson

[All he did] was (to) shake hands and wish me good luck.
[All she ever does] is (to) make jam.
[All you should do] is (to) study hard.

[The easiest thing to do] is (to) call for a taxi.
[The first thing she does] is (to) take a shower. (原句）


如果名詞片語採用doing，則is/was 後動詞也採用 Ving
What I'm doing is teaching him a lesson.

詳細說明，請見
https://ell.stackexchange.com/questions/44014/all-you-should-do-is-study-hard-vs-all-you-should-do-is-to-study-hard
https://ell.stackexchange.com/questions/35426/the-easiest-thing-to-do-is-to-call-for-a-taxi/35429#35429