If you ask me one word that I often make mistakes and have to check over again and again, that will be the word "lack", and since the way to make yourself memorise better is to write it down, I shall share this cunning word with you now.
First of all, "lack" is a transitive verb (see earlier post for more details), it is used with an object (either a single-word noun or a multi-word noun phrase):
Lack(vb) + (n)
eg. He lacks money to get marry.
eg. He is lacking confidence to propose to his beloved.
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Next, "lack" can be a noun, thus we use "of" together.
Lack of sth
eg. His lack of confidence will lower his chance of getting a job.
eg. Lack of sleep had made him fuzzy.
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However, "lacking" is an adjective, and like all other -ed/-ing adjectives, they tend to confuse the user a lot.
eg. I can't get myself to revise for my test. Interest is lacking, I believe.
Be lacking in sth (quality)
eg. He is lacking in stamina, and that is why he couldn't continue anymore after running just 2 kilometres.
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If you are clever enough, you might be asking the following question:
Is the following sentence correct?
1. "He is lacking in money."
Or should it be,
2. "He lacks money."
Then how about this one?
3. "He is lacking money."
Homework: what do you think?
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