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You can get the best result ________ you carry out the experiment under the desired conditions.

His success in his career was due to his determination __________ what seemed impossible.

However much ___________, it will be worth it.

We have got everything ready at once, with our guests _________ to come in ten minutes.

According to the research, the higher the standard of living, the ___________.

___________ the little boy John they would all have died from the gas leakage.

The task wasn’t easy, but we managed it __________.

Although he is considered to be one of the most outstanding scientists in his field, Professor White cannot seem to get his ideas ___________ in class.

Do you know by the time you leaves school your parents ________ $ 6 000 on your education.

Teaching and learning are parts of the same educational experience, but unfortunately they are often thought of ___________ separate.