Put the Verbs in the brackets in the correct forms
9. This problem (to solve) in the near future.
10. The phenomenon of radioactivity (to use) widely in industry, medicine and agriculture
11. He found that this effect (to cause) by some unknown subatomic particles.
12. The weights of these particles (to calculate) with the help of electronic computer.
13. U-238 (to convert) into plutonium and then (to use) to generate atomic power.
14. These substances (to refer to) usually as hydrogen isotopes
15. One of the isotopes of hydrogen (to call) deuterium.
16. He (to puzzle) by these unexpected results.
17. It (to show) that these substances differed greatly in their chemical properties.
18. It (to expect) that the results of our research (to apply) in chemical industry.
