Allah says:

﴿وَاضْرِبْ لَهُم﴾

(And mention) O Muhammad, to the people,

﴿مَثَلُ الْحَيَوةِ الدُّنْيَا﴾

(the parable of the worldly life), its transient nature and how it will eventually cease and come to an end.

﴿كَمَآءٍ أَنزَلْنَاهُ مِنَ السَّمَآءِ فَاخْتَلَطَ بِهِ نَبَاتُ الاٌّرْضِ﴾

(it is like the water which We send down from the sky, and the vegetation of the earth mingles with it,) It mingles with the seeds that are in the earth, so they grow and become good, producing bright, fresh flowers, then after that,

﴿فَأَصْبَحَ هَشِيمًا﴾

(it becomes dry and broken pieces,) withered up,

﴿تَذْرُوهُ الرِّياحُ﴾

(which the winds scatter.) tossing them about right and left.

﴿وَكَانَ اللَّهُ عَلَى كُلِّ شَىْءٍ مُّقْتَدِرًا﴾

(And Allah is able to do everything) He has the power to do this and that. In the Qur'an Allah often gives parables like this of the life of this world, as He says in Surah Yunus,

﴿إِنَّمَا مَثَلُ الْحَيَوةِ الدُّنْيَا كَمَآءٍ أَنزَلْنَاهُ مِنَ السَّمَآءِ فَاخْتَلَطَ بِهِ نَبَاتُ الاٌّرْضِ مِمَّا يَأْكُلُ النَّاسُ وَالاٌّنْعَـمُ﴾

(The parable of the worldly life is but that of water which We send down from the sky so by it arises the intermingled produce of the earth of which men and cattle eat. ..) ﴿10:24﴾ and in Surat Az-Zumar:

﴿أَلَمْ تَرَ أَنَّ اللَّهَ أَنزَلَ مِنَ السَّمَآءِ مَآءً فَسَلَكَهُ يَنَابِيعَ فِى الاٌّرْضِ ثُمَّ يُخْرِجُ بِهِ زَرْعاً مُّخْتَلِفاً أَلْوَانُهُ﴾

s(See you not that Allah sends down water from the sky, and causes it to penetrate the earth, then out from it comes crops of different colors.) ﴿39:21﴾ and in Surat Al-Hadid:

﴿اعْلَمُواْ أَنَّمَا الْحَيَوةُ الدُّنْيَا لَعِبٌ وَلَهْوٌ وَزِينَةٌ وَتَفَاخُرٌ بَيْنَكُمْ وَتَكَاثُرٌ فِى الاٌّمْوَلِ وَالاٌّوْلْـدِ كَمَثَلِ غَيْثٍ أَعْجَبَ الْكُفَّارَ نَبَاتُهُ﴾

(Know that the life of this world is only play and amusement, pomp and mutual boasting among you, and rivalry in respect of wealth and children. (It is) like the parable of vegetation after rain, thereof the growth is pleasing to the tiller...) ﴿57:20﴾ and in the Sahih Hadith:

«الدُّنْيَا حُلْوَةٌ خَضِرَة»

(This world is sweet and green.)