1. It has been raining since this this morning.

Question

2. It has rained since this morning.

(What is the difference between them?)

3. Tom has known the boy for two years.
4. Tom has been knowing the boy for two years.

(Are both acceptable? What about #4?)

5. He has read the novel.
(What is the meaning of this sentence?
1) He read the novel before and knows the story of the novel. 2) He has just finished reading the novel. Does #5 mean !) or 2)?)

Answer 1

#1. It has been raining since this this morning.
This means that it is still raining.
2. It has rained since this morning.
This means that sometime between this morning and now, it rained. It is not necessarily raining now.

3. Tom has known the boy for two years.
4. Tom has been knowing the boy for two years.

(Are both acceptable? What about #4?)
#4 is not acceptable usage.

5. He has read the novel.
(What is the meaning of this sentence?
1) He read the novel before and knows the story of the novel. 2) He has just finished reading the novel. Does #5 mean !) or 2)?)

He has read the novel - means that before this time he finished reading.
Either of the other two sentences can be used to say the same thing. However, the time period in which he read the novel changes. #2 means the he Just finished reading the book.