In many written languages there is a direct correspondence between combinations of letters and combinations of sounds. No doubt you have already realized that English is not such a language. Just think of the dozens of homophonic pairs and groups in English – such as lain/lane, raise/rays/raze, phase/faze and isle/aisle/I’ll.
One concept that can be hard for non-natives to internalize is that we produce the sound /ɜ:/ in a number of different ways including: -ear- before a consonant (e.g. ‘pearl’), -er- before a consonant (e.g. ‘herd’), -ir- before a consonant (e.g. shirt), -ur- before a consonant (e.g. burst) and -or- after w- and before a consonant (e.g. word). A useful phrase for fixing this idea in one’s memory is “the early bird catches the worm”, in which the vowel sound in ‘ear(ly)’, ‘bird’ and ‘worm’ is the same (not similar, exactly the same). The phrase refers to the fact that the person who takes the first opportunity to act will have an advantage over others.
 have realized – (false friend) are conscious
 such a – this type of
 just – (in this case) simply
 to lie (lie-lay-lain) – be horizontal, recline
 lane – track, path
 to raise – elevate
 to raze – burn down, destroy
 to faze – disturb, disconcert
 aisle – passageway in a church or supermarket
 hard – (in this case) difficult
 herd – group (of horses or cows)
 to burst (burst-burst-burst) – inflate and explode
 (earth)worm – (Lumbricidae) terrestrial invertebrate