This is only used in American English. It's similar to 'cut in line' and means ' jumping the queue' - in other words, not joining a queue or line at the back. For example, if the kids are lining up to get their lunch and one child pushes their way in towards the front of the queue. 'Pushing in' is the phrase I'd use in a school context. 1. You could use the present simple 'lack'. Present continuous sounds better, though - perhaps because it implies that the situation could change. 2. Yes, but the meaning is different. 'Know' would refer to your current acquaintances. 'I've known' refers to your life experiences. This would include people you met years ago.

1: Skipping lines means the people who instead of waiting for their turn tin line, do not wait for their turn but come ahead, so they skip the people already standing ahead of them . For your other 2 questions, Yes it is also correct to use the past tense, but it depends on the meaning you are trying to convey. Hope this helps. Have a great day.

It's very common to hear and use "cutting in line" as well. "Stop cutting!" "He cut in line." "Don't cut the line!" To go to the front of the queue of people rather than wait your turn in the back.

Let me rephrase the sentence "I've known people who have become food tasters" to try and explain. "I have met people who are food tasters" The context is in general terms rather than a specific instance.

We did use skipping as in "Teachers don't like students skipping ahead." Meaning that they don't want students to read beyond the lesson they've been assigned.