1. We are discussing the matter later.

2. We will discuss the matter later.
3. We are gling to discuss the matter later.
4. We discuss the matter later.
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Are they all the same in meaning? Any differences?

Even though the verbs are not all in the same tense, 1, 2, and 3 mean approximately the same thing (as long as you mean ‘going’ in 3).

4 is not used.

1. We are discussing the matter later.

2. We will discuss the matter later.
3. We are going to discuss the matter later.
4. We discuss the matter later.

Even though the verbs are not all in the same tense, 1, 2, and 3 mean approximately the same thing.

4 is not used.

1. "We are discussing the matter later" implies that the discussion is already happening, or it has been planned and will take place in the future. The verb "are discussing" is in the present continuous tense, suggesting an ongoing action.

2. "We will discuss the matter later" indicates that the discussion will happen in the future. The verb "will discuss" is in the future tense, indicating a planned action.

3. "We are going to discuss the matter later" is similar to the first sentence. "Are going to discuss" is a future continuous tense, expressing an ongoing action that will happen in the future.

4. "We discuss the matter later" is less common but still grammatically correct. It implies that discussing the matter later is a habitual action or routine. The verb "discuss" is in the simple present tense.

In summary, sentences 1, 2, and 3 convey a similar meaning of a planned or ongoing discussion in the future. Sentence 4 suggests that discussing the matter later is a regular occurrence.