Are the following sentences possible?

Thank you very much.

1) He shot me in the leg.
2) He showed me the way to the supermarket.
3) He likes shooting.
4) He shouted at him.
5) I always show my gift card to the check-out clerk so that I can get a discount on what I buy.
6)When I'm at the check-out counter, I put my shopping on the conveyor belt for the clerk to (how do you express the fact that a bar code is typed in?)
7) I had a satellite dish installed by the aerial fitter. Now I can watch English channels through my decoder (?)
8) She pretended she was't rud to Jason. She pretended not to be rude to Jason (are they both possible?)

6) scan--

When I'm at the check-out counter, I put my items* on the conveyor belt for the clerk to scan. * maybe a better word.

Yes, all of the sentences you provided are possible. Here's an explanation of each sentence:

1) He shot me in the leg.
To understand this sentence, you should know that "shot" in this context refers to the act of firing a gun, and "leg" refers to a part of the human body. Therefore, someone (not specified in the sentence) shot the speaker in their leg.

2) He showed me the way to the supermarket.
In this sentence, "showed" means the person directed or guided the speaker to the supermarket. "Me" indicates that the speaker was the one who received the guidance, and "the way to the supermarket" means the path or route to reach the supermarket.

3) He likes shooting.
This sentence states that the person mentioned enjoys the activity of shooting. The context of the word "shooting" is not specified, so it could refer to shooting with a gun, shooting photographs, or some other activity involving shooting.

4) He shouted at him.
This sentence implies that one person raised their voice in a loud, forceful manner directed towards someone else. It indicates that the person mentioned as "he" directed their shouting at the person referred to as "him".

5) I always show my gift card to the check-out clerk so that I can get a discount on what I buy.
This sentence describes a habitual action. The speaker always presents their gift card to the check-out clerk, which allows them to receive a discount on their purchases. The purpose of showing the gift card is to obtain a price reduction.

6) When I'm at the check-out counter, I put my shopping on the conveyor belt for the clerk to (how do you express the fact that a bar code is typed in?)
This sentence explains an action that the speaker takes while at the check-out counter. They place their purchased items on the conveyor belt, and the purpose is for the check-out clerk to scan the barcodes on the items. In this context, "typed in" isn't the most accurate expression. It would be more appropriate to say "scan" or "read" the barcodes.

7) I had a satellite dish installed by the aerial fitter. Now I can watch English channels through my decoder (?)
This sentence describes past events. The speaker had a satellite dish installed, likely by a professional called an "aerial fitter." The purpose of installing the dish was to enable the speaker to watch English channels through their decoder. The term "decoder" implies that there is a device used to decode the satellite signal and display the channels on the speaker's television.

8) She pretended she wasn't rude to Jason. She pretended not to be rude to Jason (are they both possible?)
Both variations are possible and convey a similar meaning. The first sentence "She pretended she wasn't rude to Jason" suggests that she acted in a way that did not come across as rude to Jason, but there is a possibility that she actually was rude. The second sentence "She pretended not to be rude to Jason" has a similar meaning, but it emphasizes that she actively avoided being rude towards Jason.