Reflexive Pronouns

Click the most suitable reflexive pronoun. If it is not possible to put a reflexive pronoun click (---). EXPLANATION
1) He put his briefcase next to him | himself. RULE#3
2) "Can I have another drink?" "Of course. Help yourself | you!" RULE#5
3) Ann wasn't careful and cut her | herself with a carving knife. RULE#2
4) I can't believe it! The president himself | him answered the phone. RULE#4
5) Make you | yourself at home while I go and find those books. RULE#5
6) I can't concentrate (---) | myself with all that noise going on. RULE#1
7) Linda came back looking very pleased with herself | her. RULE#2
8) I've made this decoration by me | myself. Nobody's helped me. RULE#4
9) Let's just relax and enjoy (---) | ourselves. RULE#5
10) He tried to kill himself | him with sleeping pills. RULE#2
11) They often complain themselves | (---) about not feeling appreciated at work. RULE#1
12) Martin always repairs his motorbike by himself | him. He says he can't afford to pay a mechanic to do it. RULE#4