I had finished my work before he returned.
After the sun had set, we decided to return home.
We had reached the station when the rain started.
He thanked me for what I had done for him.
The manager had not left the office before I arrived.
We had written the article by five o'clock.
By the end of the year she had learnt to speak English.
We sent him a telegram yesterday as we had not received any letters from him for a long time.
After he turned off the light, he left the room.
<span>He had been away for several months before his first letter came.</span>
2) Experienced freedivers can easily hold their breath for a long time.
3)Taxi drivers have to know a city well so they can find people's destions.
4)The secretary types slowly in order to avoid making mistakes.
5)Security guards often work lately at night guarding buildings.
6)Forest fires can start <span>suddenly</span> in very dry areas.
Hello, my dear!
My family is funny! Today is I and my family goes to the cinema!
I like cinema, it’s funny! My dad today walk to the park, my man today coockie pie, my brother meet friend, I goes to scoop and visit my grandmam and pap
1. Do several examples denonstrate this idea?
2 Will you study amplifier circuits at the next lecture?
3. Did the device calculate the frequency of electromagnetic waves ?
4. Does the frequency of free oscillations of an open tuned circuit depend upon its capacitance and inductance?
5. Did operators make all the connections by hand place in the early days of telephone?
6. Will/won't the waves cancel each other and will considerable radiation take ?
7. Did the detector completely cut off one-half of the wave?
8. Do energy losses take place in any aerial?
9. Are glass fibers cheaper and lighter than copper wires?
10. Did the automatic station "Zond-7" maintain stable?