Hello native English speakers.
Could you do me a favour and help me for my queries about two sentences.

1a. The sea has eroded the cliff face over the years.
( This is a complete sentence)
1b. The sea's erosion of the cliff face over the years.
( This is a noun phrase)
1c. The erosion of the cliff face by the sea over the years.
( This is a noun phrase)

Question:
Are they all grammatically correct?
Can these "expressions" be suggested the same meaning?

2a. Tom furtively ate three apples last week. ( This is a complete sentence)
2b. Tom's furtively eating three apples last week. ( This is a noun phrase)
2c. Tom's furtive eating of three apples last week. ( This is a noun phrase)
2d. For Tom to eat three apples furtively last week.
(This is a noun phrase expressed by infinitive)

Question: Are they all grammatically correct?
Can these "expressions" be suggested the same meaning?

Question

Hello  native English speakers.
Could you do me a favour and help me for my queries about two sentences.

1a.  The sea has eroded the cliff face over the years. 
( This is a complete sentence)
1b. The sea's erosion of the cliff face over the years.
( This is a noun phrase)
1c.  The erosion of the cliff face by the sea over the years.
( This is a noun phrase)

Question: 
 Are they all grammatically correct?
Can these "expressions" be suggested  the same meaning?

2a.  Tom furtively ate three apples last week. ( This is a complete sentence)
2b.  Tom's furtively eating three apples last week. ( This is a noun phrase)
2c. Tom's furtive eating of three apples last week. ( This is a noun phrase)
2d. For Tom to eat three apples furtively last week.
(This is a noun phrase expressed by infinitive)

Question: Are they all grammatically correct?
Can these "expressions" be suggested  the same meaning?

Answer

1. Erosion Sentences
✅ All are grammatically correct.
🔹 1a (sentence) and 1b/1c (noun phrases) express the same idea but in different structures.

2. Eating Sentences
❌ 2b is incorrect – "furtively eating" doesn’t fit naturally in a noun phrase.
✅ 2a, 2c, and 2d are correct but differ slightly in focus.
🔹 2c (Tom's furtive eating of...) is the most natural noun phrase.
🔹 2d (For Tom to eat...) sounds more abstract, often used when explaining reasons.

Answer

(1) All can be correct, and all can be a valid response with practically the same meaning, to a question like: "What caused the cliff face to change so much?"

(2) All can be gramatically correct, and A, B & C could all answer this question, to convey a similar meaning: "What made my apples disappear so fast?" But 2D would not answer the same question appropriately. "For Tom to..." would answer a different kind of question, for example: "Why did you collect more apples than we could count?" or "Why did you leave the kitchen door unlocked?"