When using the English language "always" is very rarely applicable. You will invariably find an exception to any rule.
However, where the prefix de- is being used to indicate removal of something, as in your examples, the pronunciation is with a long vowel dee-. This applies in most regional variants of English.
If the word simply starts with de, for ...
While batsmen may hit/score/take two runs or make two runs, they DON'T run two runs. It's not idiomatic.
Instead, as you suggest, ran two is fine when the context is already established. You will often hear expressions such as:
they take an easy two....
they scurry home for two...
they snatch two (runs)....
and so on.
Your sentence is correct as it stands. "Already" can be used with the present tense:
I am already in London.
I already play tennis, so I'd like to learn squash.
You could consider using the present perfect in your example:
You have to choose an hour that hasn't already been taken by someone else.
Neither of these is wrong, and the obviously intended meaning is the same. To me as a native speaker of US-English
I came here from England for my education
seems much more natural. The other sentence:
I came here for my education from England
tempts a reader to parse "my education from England" is if the education somehow came from England. A ...
Carrying coal[s] to Newcastle is known in the U.S., but at this writing I cannot recall the last time I have actually heard it come out of anyone's mouth, either in real life or in films or television (I have lived almost my entire life in Southern California and the Mid-Atlantic region). I do see it from time to time in writing and in foreign usage. The ...
I shall / he will is, I think, still common amongst older people who were taught a more formal style of English. I use it myself (and it is my natural register) but when teaching English to speakers of other languages we (the tutors and helpers in classes) only teach and use will. Fewer people would naturally use the corresponding I will / he shall form to ...
As a verb I would use two words, this allows for the verb endings to be added easily.
My connection timed out after 30 seconds.
As a noun I would use a compound word:
We should increase the timeout to 45 seconds.
Using a hyphen would be an entirely acceptable alternative.
I agree. A 30-second time-out is too short.
The word "shall" is used much less often than "will" in modern English, with some notable exceptions. You should use "will" in almost all contexts.
Religious speeches, text, and pronouncements tend to use "shall" or "shalt", especially in parodies. "He shall repent" is an example of this. Commands from God (such as the Ten Commandments) will almost ...
Using shall instead of will in the first sentence expresses certainty (he will certainly repent).
The British traditionally use shall to express determination or
intention on the part of the speaker or someone other than the subject
of the verb.
He should repent is a supposition ...
Syllabification side point
This is a side point, but one thing to keep in mind is that even with a short i sound, "decode" would not be pronounced like "Dick-oh-d". You may have heard a rule about "short" vowel sounds being grouped with a following consonant, but that rule only applies when in syllables that have some degree of stress. A short vowel sound ...
He left, although I begged him not to.
He left, but I begged him not to.
He left, and I begged him not to.
These three sentence do not have the same meaning, and the first is far more natural than the other two.
The first means "He left, in spite of my begging him not to." In short the begging did not have its expected or desired effect.
The second ...
Carrying coals to Newcastle.
Is familiar to me, but although I am a US native, I have read a lot of works of BrE
This that should be understood widely might might include:
Bringing sand to the beach.
Bringing sand to the Sahara.
Taking ice to Antarctica
Importing gold to South Africa.
None of these have the idiomatic status of "coals to ...
Many have suggested that this points to a activity in futility whereas it is actually a comment on the lack of necessity. I was born and raised in RI and have been familiar with this phrase all of my life. I believe that those from the East coast (especially New England) would have a greater familiarity. I grew up in a home where coal was delivered through a ...