The most common colours we can see are brown,white and black. 這句英文是否有錯，因為它張兩個動詞放在同一句中(see和are )唔喺同一句裏不能有兩個動詞嗎?請指教?

此句的完整句子是The most common colors which we can see are brown,white and black.
which we can see 是形容詞子句,用來修飾colors, 所以並無二個動詞的問題,因為這是二個句子合成一個句子的結果,主要子句為The most common colors are brown,white and black.形容詞子句是which we can see (在此which因為是受格關代,所以被省略了. ^_^)

The object of the verb is a" that-clause"." That" is often omitted when placed after the subject:-
The most common colors are--------subject +vt
(that) we can see-----that-relative pronoun in restrictive clause after "colors"
brown,white and black--------complement to subject+vt

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