Questions

The EKG was invented by Willem Einthoven in 1903 and is used to monitor and analyze past and present heart activity in an individual.

In the above given sentences, only option C) The hen has laid 10 eggs is gramatically correct.

A) Not correct - We had gone to the party last night

Correct - We went to the party last night

B) Not correct - I have seen him yesterday

Correct - I saw him yesterday (We do not use the present perfect tense with past time expressions.)

D) Not correct - She is sleeping for 2 hours

Correct - She has been sleeping for two hours. (We use the present perfect continuous tense to show duration.)

Some common foodborne illness are like vomiting, diarrhea, fever, chills and abdominal pain. These all are acute i.e, they last for only some time and be cured without medication and some times by medication.

The words do, does and did often cause confusion in the English language. They are all forms of the verb to do.

It is also common to use do, does and did as auxiliary verbs (or helping verbs) together with another verb in its base form. This is used to create negative sentences, questions, or for adding emphasis.

Examples :: 

* Russel did a great job on his debut match for team.

* Did you catch the train this morning?

* When did they arrive home?