1. occur
Overlap can occur.
A budget deficit will occur because of a revenue shortfall.
These structures would rarely, if ever, occur in spoken English.
The important point concerning the complementary distribution is to specify the environment where the individual sounds occur.
Precognition is the act of using spiritual-power to know things that will occur in the future.
Some English speakers think that omission of the subject does not occur in their language, however, the subject of phrases like "thank you" or "bless you" is omitted.
The President cannot make clouds to rain and cannot make the corn to grow, he cannot make business good; although when these things occur, political parties do claim some credit for the good things that have happened in this way.
Pet loss refers to the reactions of shock and anger that occur in owners who have been bereaved of their pets.
It's the prevention of migraines during daily life that's important, not dealing with migraines when they occur.
The World Meteorological Organisation reported that 2000–2009 was the hottest decade on record, with eight of the hottest 10 years having occurred since 2000.
The first reference occurs in the English poet William Langland's book Piers Plowman written between 1370 and 1390.
Anup Kaphle recently pointed out that violent protests have occurred in countries such as Bosnia, Thailand and Guinea, among others
Many instances of hypothermia occur inside when there is cold weather and a lack of heating.
There is a downside to this: painful and unpleasant memories are as vivid as if they had just occurred.
Every airplane has an angle of attack where maximum lift occurs.
2. happen
If you know that something unpleasant will happen, that you will go to the dentist for example, or to France, then that is not good.
what's happening?
He was so healthy up to the minute of his sudden death. You really never know what might happen next.
Suppose there was a worldwide oil shortage in ten years' time. What would happen to the industrialised countries?
If a tree falls in a forest and nobody hears it, did it happen? If a man speaks his mind in a forest, and no woman hears him, is he still wrong?
There are many uses of the 'present tense' of Japanese grammar which indicate things yet to happen.
How does it happen that you were not eaten up with all those hundreds and trillions of cats?
I'm sorry, but do you happen to have the key to that machine over there? My croissant is stuck.
I just got a great job because of an introduction from a friend. Sometimes things happen when you least expect it.
Wealth comes to those who make things happen, not to those who let things happen.
That shan't happen again, Fortunatus said to himself, and they started to ride at each other again. This time, Fortunatus's spear met his foe so powerfully that he flew from his horse like a ball and lay dead on the earth.
(be) Tom happened ... at Alan's when I called in so I invited him to our party as well.
To my chief strategist, David Axelrod, who's been a partner with me every step of the way. To the best campaign team ever assembled in the history of politics! You made this happen, and I am forever grateful for what you've sacrificed to get it done.
3. happen to
the worst thing that can happen to a man like him
If you happen to spill, wipe off immediately.