While writing, make sure all facts are in the present simple, not the continuous. ESL students have a tendency to overuse the present continuous tense. The present continuous tense should only be used for actions that are in progress or happening at the moment of speaking. Use the simple present tense, not the present continuous, for proven facts. By proven facts we mean actions or states that are always true.
Study the examples given below.
- Water boils at 100 degree Celsius. (NOT Water is boiling at 100 degree Celsius.)
Here we are talking about something that has been proved by scientists.
Sometimes we boil water to make tea or cook meals. Read the sentence given below.
- The kettle is boiling. Shall I make tea? (NOT The kettle boils. Shall I make tea?)
Here we are talking about something that is happening at the moment of speaking. Hence the present continuous tense is used.
Other examples illustrating the correct use of the simple present and present continuous tenses are given below.
- Heat expands bodies. (NOT Heat is expanding bodies. It’s a proven fact.)
- The sun rises in the east. (NOT The sun is rising in the east.)
- Plants need water and sunlight for proper growth. (NOT Plants are needing water and sunlight for proper growth.)
- When volcanoes erupt they shoot lava into the air. (NOT When volcanoes are erupting they are shooting lava into the air.)
- John plays the piano well. (Here the reference is to a fact.)
- Who is playing the piano? (NOT Who plays the piano?) (Here the reference is to an activity that is happening right now.)
- My sister writes excellent short stories. (A fact)
- My sister is writing a story now. (An activity that is going on at the moment of the speaking.)
Now read the sentence given below.
- My sister has written many short stories.
As you can see, this sentence is the present perfect tense. Neither simple present nor present continuous tense is possible in this case because here we are talking about an action occurred at an unspecified time in the past.
- She has eaten twelve candies since morning. (NOT She is eating twelve candies …) (NOT She eats twelve candies…)