The Aya says:
Indeed, what those are in is broken up and null is what they do.
My personal note:
The root T-B-R is the one used for the raw gold that collected broken and scattered over wide areas. It is used for something broken into smithereens and destroyed.
The Aya basically reiterates the main them of the Qur’an that any work one does with the aim is other than God is countless and eventually has no benefit for the person doing it. Therefore it ends up in spent useless effort.
Some early Muslims mentioned that the best work a person does is the most sincere and the most correct. Most sincere is where the intention is purely for Allah and most correct is when the action is most adhering to the instructions of Allah and His messengers.
Translation of the transliterated words:
Mutabbarun: broken up/ scattered
Note: the root is T-B-R and it means raw gold when it is found in broken and scattered little pieces over the earth and in river beds and so on. Conceptually, the term is used for anything that is broken and scattered in thousands of pieces. MUTABARUN means broken up/ scattered.
wabatilun: and failed/ and obsolete/ void/ null
Note: WA is a letter that links what is before with what is after. This link is through inclusion, either one is included in the other or they are all included in the bigger sentence or bigger picture. WA often corresponds with “and/ addition” but the more encompassing meaning is in inclusion one in another or all in a bigger picture or sentence. BATILUN is derived from the root B-TTa-L and it means null or void or naught.
Kanoo: they happened to be/ they were
Note: the root is K-W-N and it means being. KANOO is an action that is completed that is derived from the root. It means: the action of being happened by the subject (third personal plural). This in turn means: they were or they happened to be
yaAAmaloona: they do/ to do
Note: the root is Ain-M-L and it means doing or work. YaAAaMALOONA is an action that is being completed or will be completed. It means: the action of doing or making is happening or will be happening by the subject (third person plural). The combination of KANOO YaAAMALOON gives the impression of this: they happened to be doing or they happened to do.
Salaam all and have a great day.