Chance and Nature(U12/DC1-C2).

act of God

-an event caused by natural forces beyond human control,such as a storm,a flood or an earthquake

come rain or shine

whether there is rain or sun,whatever happens

down on your luck

to have no money because of a period of bad luck

draw the short straw

be chosen to do sth unpleasant

have green fingera

to be good at growing plants

let nature take its course

to allow nature processes to happen without trying to stop or change them(used especially in the context of illness)

there’s no rhyme or reason(to/for sth)/without rhyme or reason

used for emphasizing that there is no reason or explanation for sth

out of the blue

unexpectedly;without warning

the luck of the draw

the fact that chance decides sth,in a way that you cannot control

touch wood

usee when talking about your previous good luck or you hopes for the future,to avoid bringing bad luck