This sentence incorrectly uses quotation marks to set off an indirect quotation from the sentence when no quotation marks are needed. If the sentence said "Liam told his study group, 'I need to take a break from studying,'" then quotation marks would be necessary. However, because the sentence is indirectly telling us what Liam said, and not giving us his exact words, no quotation marks are needed. Removing the quotation marks around "he needed to take a break from studying" would correct the sentence's error.

Punctuation always goes inside the quotation marks in American English.

The sentences uses quotation marks for an indirect quotation from Daniel when no quotation marks are needed. Only direct quotations require quotation marks in sentences like these.

Jose's direct quote ends with an exclamation point, so the quote does not require a comma to separate it from the rest of the sentence.

Placing the comma outside of the end quotation marks in a direct quote is incorrect in American English. The comma should immediately follow "America" in the above sentence.

因为sentence inside the quotation marks is a question, it must be punctuated with a question mark. This question mark should appear inside the quotation marks, as follows: “Did you see where that dog went, and can you help me follow it?”

这句话是完全打断。因为sentence of speech is broken up in the middle with a dialogue tag, commas are used after “you” and after “said” to set off that dialogue tag. (If the spoken part was two sentences long, however, you would have to use a period after “said” and a capital B for “but,” since you would be starting a new sentence after the dialogue tag.)

Quotation marks should only be used to set off direct speech from the rest of a sentence. In this case, the speaker is recalling what he or she usually tells his or her coworkers, and he or she is doing so using indirect speech. Indirect speech never requires quotation marks, so there should be no quotation marks in this sentence.

This sentence is properly punctuated and contains no errors. Because the sentence is using direct speech—in other words, it’s recounting exactly what Anna said to her mother—quotation marks and a comma are necessary to offset the direct speech from the rest of the sentence.

因为sentence inside the quotation marks is a question and already contains a punctuation mark, the comma that appears immediately after the quotation marks is redundant. Only the question mark (properly placed inside the quotation marks) is necessary.