Open the brackets and write only the verb forms with the subject in past simple (positive sentences or questions): 1. i sally about my dress. (to ask) 2. what for this party? (they/ to buy) 3. sam in the bank yesterday. (to be) make on-the-spot decisions. write your sentences with full verb forms, use full stops: 1. the phone’s ringing. (not answer it/i) 2. it’s cold here. (he/wear/a jumper) 3. it is very expensive here. (she/not/ live/ in this country) here are the verbs. write the second form of these verbs. example 0. grow answer 0. grew 1. to have 2. to make 3. to show
1 The internal combustion engine is called so because fuel is burned
directly inside the engine itself
2 To describe the complete cycle, let's that the piston is
the top of the stroke (top dead center) and the and the exhaust
valves are closed, When the piston
moves down the inlet valve opens to
intake a charge of fuel into the cylinder. This is called the inlet (intake)
stroke.
3 On reaching the lowest position (bottom dead center) the pis-
der,
begins move upward the closed upper part the cylinder,
the valve is closed and the mixture is compressed by the rising
piston. This is called the compression stroke.
4 Asthe piston again
the top dead center the spark plugs ignite the mixture, hoth valves he
ing closed during its combustion. As a result of burning mixtures the
gases expand and great pressure makes the piston move back down the
cylinder. This stroke is called the
reaches
powerstroke
5 When the piston reach
the bottom of its stroke, the exhaust valve is opened, pressure is re-
lensed, and the piston again rises. It lets the burnt gas flow through the
exhaust valve into the atmosphere. This is called thexhaust stroke
which completes the cycle
6 So the piston moves in the cylinder down
(intakestroke), up (compression stroke), down (powerstroke), up (ex-
hanst stroke)
1 a
2 a
3 b
4 a
5 b
6 a
Объяснение: