As a maritime nation, the british were concerned with one problem in particular: they could make clocks that kept very good time as long as they stayed perfectly still but not when they were shaken about, and particularly not on board a rolling ship. if you wanted to sail, it was impossible to keep a precise record of time.

compare & contrast informative essay/speech

when speaking or writing for the sole purpose of providing information in order to give audience members a good basis for making a decision, you would present an informative speech or essay.   because you wouldn’t want to be persuading the audience by arguing for one type of exercise over the other, you wouldn’t choose a persuasive/argumentative technique.   to fairly, and without bias, present information about the pros and cons of each type exercise, a compare/contrast, informative speech/essay would be the best bet.

the present continuous is a verb tense which is mainly used to indicates that an action is in progress at the moment of speaking.  

it is formed using: person + verb to be (am/is/are) +verb + - ing form  

example: i am studying at this moment .

in addition, the present continuous is also used in order to express things that will or will not happen in the near future.

example: i am having dinner with some friends tonight.

the speaker sometimes   uses it   to express that an action is repeated and it causes irritation on the part of the speaker

example: my sister is constantly complaining about everything.