1. Teacher shake me by the shoulder when I am sleeping in class.

2. The teacher shakes me by the shoulder when I am sleeping in the class.

(Is #1 right? What about #2? Do we have to use 'in class' or 'in the class'?)

No, #1 is not correct, but if you make the verb "shakes," it'll be correct.

Just "in class" is all you need. The article "the" isn't needed.

Teacher shakes me by the shoulder when I am sleeping in class.

(Thank you for your help. The teacher ot Teacher? I think 'The teacher' is correct? Am I right? Can we use 'Teacher' in this sentence?)

The sentence is definitely better with "The teacher..." at the beginning, yes. I've heard the other wording, but not very often.

Both sentences convey similar meaning, but there are slight differences in their structure and word usage.

1. "Teacher shake me by the shoulder when I am sleeping in class."

This sentence is grammatically incorrect because the verb "shake" should be written as "shakes" to agree with the singular subject "teacher." Additionally, it is more common to use the definite article "the" before the noun "teacher" to specify a particular teacher rather than a generic one. Therefore, the corrected version of the sentence would be: "The teacher shakes me by the shoulder when I am sleeping in class."

2. "The teacher shakes me by the shoulder when I am sleeping in the class."

In this sentence, the phrase "in the class" is used to specify the location where you are sleeping, which is inside a specific class. By using "the," it implies that you are referring to a particular class or a specific class setting. However, it is more common to use "in class" without the article "the" to refer to the general act of being in a class or a classroom. Therefore, a more natural way to phrase this sentence would be: "The teacher shakes me by the shoulder when I am sleeping in class" or "The teacher shakes me by the shoulder when I am sleeping in class."

In summary, both sentences can be corrected to say "The teacher shakes me by the shoulder when I am sleeping in class," but the second sentence is more commonly used without the article "the" to refer to a generic class or classroom setting.