Due
to means"cause by". It shoud only be used if it can be substitued with "caused by".

It doed not mean the same thing as "because of ",

Incorrect: The game was postponed due
to rain.

Correct: The game was postponed because of rain.

Correct: The game's postponement was due
to rain.

以后再遇到due
to只要把它换成我们熟悉的caused by就清楚多了。

"Due
to” modifies nouns and often follows “to be” verbs (is, was, were, am, etc.).

Example: My loss of appetite was due
to a stomachache.

In this case, “due
to” modifies “stomachache” and follows the to be verb, “was.”

"Because of,” on the other hand, modifies verbs.

Example: I lost my appetite because of a stomachache.

To be more precise, with their attendant words, “due to” and “because of” operate as adjectival and adverbial prepositional phrases. To understand how the functions of “due to” and “because of” vary, look at these sentences.

1. His defeat was due to the lottery issue.

2. He was defeated because of the lottery issue.

     In sentence #1, his is a possessive pronoun that modifies the noun defeat. The verb “was” is a linking verb. So, to create a sentence, we need a subject complement after the verb “was.” The adjectival prepositional phrase “due to the lottery issue” is that complement, linked to the  subject by “was.” Thus, it modifies the noun defeat.
     But in sentence #2, the pronoun "he" has become the sentence's subject. The verb is now “was defeated.” As reconstructed, “He was defeated” could in fact be a complete sentence. And “due to” has nothing to modify. It's an adjective, remember? It can't very well modify the pronoun “he,” can it?
     Neither can it refer to “was defeated” because adjectives don't modify verbs. Sentence 2, therefore, should read: “He was defeated because of the lottery issue.” Now the “why” of the verb “was defeated” is explained, properly, by an adverbial prepositional phrase, “because of.”
     In informal speech, we probably can get by with such improper usage as “His defeat was because of the lottery issue,” and “He was defeated due to the lottery issue.” But we shouldn't accept that kind of sloppiness in writing. We don't want to look stupid among those in the audience who know better. If we show them we don't care about the language, how can we expect them to believe us when we tell them that we care about the facts