Найдите герундий, в какой форме он используется:
1)The teacher insists on carrying out this experiment in our laboratory
2) Upon carrying out a number of expe-riments our students solved many interesting problems.
3) By using this law we define a unit change of electricity.
4) Heating the wire from 0 ̊ to 100 ̊ in-creases its resistance approximately by 40 %