Check yourself

1. Read the text and retell it in the Present Simple using the questions below as an outline.

The principle of science, the definition, almost, is the following: The test of all knowledge is experiment. Experiment is the sole judge of scientific “truth”. But what is the source of knowledge? Where do the laws that are to be tested come from? Experiment, itself, helps to produce these laws, in the sense that it gives us hints. But also needed is imagination to create from these hints the great generalizations – to guess at the wonderful, simple, but very strange patterns beneath them all, and then to experiment to check again whether we have made the right guess. This imagining process is so difficult that there is a division of labor in physics: there are theoretical physicists who imagine, deduce, and guess at new laws, but do not experiment; and then there are experimental physicists who experiment, imagine, deduce, and guess.

(R. Feynman)

1. What is the principle of science?

2. What is the role of experiment and how does it help to produce the laws?

3. What does one need to create the great generalizations?

4. What division of labor is there in physics and why is it necessary?

5. What is the difference between theoretical and experimental physicists?

2. A) Decide which time expressions from the box below go together with the Past Simple which refers to a definite time in the past.

for, since, ago, in 1980, just, recently, at 10.00, yesterday, last, never, before, already

b) Fill in the gaps with the correct verb.

He his first lecture on physics in 1980.	make give participate observe suggest write begin get
I first in an international conference two years ago.
He this effect in 1991.
We this method last year.
He interested in physics last year.
He to study the nature of this phenomenon long ago.
They a joint paper in 1998.
He a report at the conference yesterday.

3. Change the following sentences into the Present Perfect using ‘just’, ‘already’, ‘recently’, ‘yet’, ‘never’, ‘ever’, ‘lately’.

1. They found similarities between the phenomena under study. (recently)

2. Physics made great advances in the investigation of this problem in the 20^th century. (already)

3. He wrote a scientific paper a month ago. (just)

4. Did you send the editor a copy of your paper last week? (yet)

5. I attended seminars on superconductivity last year. (never)

6. Did you visit their research laboratory? (ever)

4. Make as many sentences with the Present Perfect as possible from the chart.

Atomic physics High energy physics This laboratory The conditions for research work Scientists

considerably improve become a large research center develop into an independent area make good progress work out a better approach establish new facts

during / in the past few years during / in the last decade in recent years