In the given sentences, let's check the underlined verbs for correctness:
(1) Water boils at 100 degrees Celsius.
- The verb "boils" is correct here as it describes a scientific fact.
(2) How often are you going to the cinema?
- The verb "are going" is correct as it indicates a future action.
(3) Martina is phoning her mother every day.
- The verb "is phoning" is correct to show a recurring present action.
(4) I must go now! It gets late.
- The verb "gets" should be changed to "is getting" to maintain consistency in the present continuous tense.
(5) Paul is never late. He's always starting work on time.
- The verb "is starting" should be used instead of "starting" to match the present continuous tense.
Regarding the present tenses "I am doing" and "I do" with a future meaning:
Present continuous (I'm doing) with a future meaning:
- We use the present continuous tense to talk about planned future actions, such as "I'm meeting my friend tomorrow."
Present simple (I do) with a future meaning:
- The present simple tense is used for scheduled events in the future, like "The train leaves at 7 p.m."
By understanding the differences between these tenses, you can accurately convey future actions using present forms in English.