Перепишите следующие предложения и переведите их на русский язык, обращая внимание на функцию инфинитива.

1. The programmer must do a program to give accurate instructions to the computer.

2. Electric typewriters are very slow and are used only by operators to communicate with a computer.

3. The machine to operate with the keys is named an ordinary adding machine.

4. The programmer to do the program for a computer must have a good knowledge of mathematics.