Into and In To, Onto and On To, Upon and Up On…
Into and In To
The word into has many meanings and contexts, so I shall pick the most common.
into (preposition)—expressing movement or action from one place to another; the direction something is turned towards upon contact with something else; indicating a route taken; expressing a change of state; indicating an object or subject of attention; and expressing an active interest in something
Manon turned off the light and got into bed.
The shopping trolly crashed into the parked car.
The widow cried into her apron.
‘We should’ve taken the road down into the town!’ the woman complained.
‘I watched you change into a fly,’ Chino sang.
The committee was going to look into the problem but they never did.
‘Man, William is so into you!’ Caitlin giggled.
Out of the frying pan, into the fire.
However, in other sentences, the words in and to just happen to find themselves situated next to each other. For example:
The bowl was placed before them all. Josh wanted to put his name in to see whether he would get picked for the team.
The child slipped and fell into the pool. Matilda dived in to save the drowning child.
In situations like these, the to belongs to the verbs see and save and the in serves as a preposition relating to an object previously mentioned—the bowl and the pool.
If you are still unsure whether into or in to should be used, try to read the sentence with a slight pause between in and to. If it sounds awkward, as the first seven examples do, then it’s probably best to use into. However, the last two examples sound fine with a slight pause and, in fact, should be spoken and read with one in any case.
Another way to establish which to use is to ask a question in the middle of in to. For example:
Josh wanted to put his name in… WHY? …to see whether he would get picked for the team.
Matilda dived in… WHY? …to save the drowning child.
Onto and On To
Onto and on to follow the same rules as those which govern into and in to.
onto (preposition)—moving to a position on the top of something; or boarding transport
Shannon clambered up onto the box.
The cat leapt onto the bed.
Fifi hopped onto the tram.
In some situations, ‘on’ and ‘to’ are neighbours in a sentence. Such as:
‘I got on to see whether Tom was on this tram,’ Fifi admitted.
Despite being late, Stacey continued on to the station.
In these instances, on belongs to the verbs got and continued. In the first example, to belongs to the verb see, but in the second example, to is a preposition expressing the movement towards the station.
We can also ask questions of on to as we did with in to.
‘I got on…’ WHY? ‘…to see whether Tom was on this tram,’ Fifi admitted.
Despite being late, Stacey continued on… WHERE? …to the station.
Upon and Up On
upon (preposition)—a more formal term for on, particularly used in an abstract sense
The artefact was placed upon the altar.
We must uphold the rules and traditions upon which this empire was founded.
But like on to and in to, up and on sometimes find themselves next to each other in a sentence while also being entirely separate.
Angela put the lollies all the way up on the highest shelf in the pantry.
‘I’ll just look it up on the Internet.’
I felt like watching a movie, so I grabbed From Up On Poppy Hill.
I hope this has helped! Good luck!