Consider 的主要意思有三：
第一義是「認為，把…視為」(句型為：consider + 受詞 + 名詞/形容詞)。例如：Do you consider her suitable for the job? (你認為她適合做這份工作嗎?)。
第二義是「考慮，細想」。例如：We will not fail to consider your feelings on the matter. (我們不會不考慮你對這件事情的感受)。
第三義是「考慮到；考慮過」。例如：I have considered all aspects of the problem. (我已考慮過這問題的所有層面)。
由於第一義與 regard as 和 view as 同義，所以當 consider意為「認為，把…視為」時，就不可在其後加上 as (但若意為「考慮」，則可加上 as)，但可加上 “to be” (可省略)：
I consider it (to be) a great honor to be invited to join the club. (我認為被邀請加入此俱樂部是很大的榮幸) (正)
I consider it as a great honor to be invited to join the club. (誤)
最後要提的是，consider 後面若接動詞，須用動名詞而非不定詞：
I’m considering changing my job. (我正考慮換工作) (正)
I’m considering to change my job. (誤)
上面對consider用法的說明不完全正確
consider 意為「把…視為…」有時是可以接as的。
Oxford Advanced Learner’s Dictionary 對consider
的解釋中即列出 consider sb/sth (as) sth 的用法，並且舉出
These workers are considered (as) a high-risk group的例句。
另外 Michael Swan在他的名著Practical English Usage 155節中
也對consider提出下面說明:
Consider + object (+as) … (=’think of somebody or something as…’)
並舉 He always considered her (as) his real mother 的句子
為例。
可見如果意為「把…視為…」而且用於consider somebody/something (as) somebody/something的句型時是可以用as的，不過不用as或用to be 也是正確的。
Active voice: Farmers traditionally consider the Lunar New Year (as/to be) the true beginning of a new year. (1)
Passive voice: The Lunar New Year is traditionally considered (as/to be) the true beginning of a new year by farmers. (2)
In conformity with the SVOC sentence pattern in sentence (1), the object complement could have three options: (i) a noun phrase “the true beginning of a new year”, (ii) a prepositional phrase “as the true beginning of a new year”, and (iii) an infinitive phrase “to be the true beginning of a new year”.
In the spirit of conciseness advocated by Rhetoric, the preposition “as” and the infinitive phrase “to be” could be left out of sentences (1) and (2).