一個英文問題 - 一句有兩個動詞?

In fact, there is only one verb in each sentence. In your examples, smile, feel and want are actually not verbs, they are all infinitives without to.
After the verbs, make or let, the infinitives without to are used. That's why they are mistaken as 'verbs". But they are not "verbs", they are infinitives.
Other similar sentences:You help me work = You help me to work.
Go get the book = Go and get the book. = Go to get the book

當主動作main verb與另一動作infinitive=to+verb. 必定是即時/同時存在時.

就要將"to"隠藏. 因爲to+verb=infintive的時態特性是遲于主動詞.
若不隠藏就有矛盾.

舉例某些動詞(vt) hear-see-watch-notice-observe-feel-let-make等動詞
後面的[不定詞]短語, "to"要隠藏.

eg. I hear a bird (to) sing in the tree.
......Yesterday I saw him (to) fly a kite.

主動詞之後那個是[infinitive不定詞without (to).不是 verb.