Could you check this?

Question

Complete the questions. I wrote my answers with capital

1. Researchers are SUPPOSED TO BE VERY careful when working in the lab.
2. They ARE SUPPOSED TO CHECK and recheck dangerous experiments.
3. They are SUPPOSED TO THINK before acting impulsively.
4. Researchers ARE SUPPOSED TO panic when things go wrong.
5. The lab is SUPPOSED TO SHUT DOWN automatically if it is contaminated.

thanks

Answer 1

All look good except for 4.

Answer 2

Researchers AREN'T SUPPOSED TO panic when things go wrong.

Answer 3

Right. :-)