Examples:

(a) a bicycle

(b) a year

(c) a useful tool

(d) a university

Note: University is read as 'Yew-ni-ver-si-ty', thus it starts with a 'yew' sound not a 'u' sound. 

Examples:

(a) an umbrella

(b) an event

(c) an orange

(d) an hour 

Note: Even though 'hour' starts with the letter 'h', which is a consonant, the word is read as A-WER. The 'h' sound is not pronounced.) 

1. The bicycle I lost was a present from my dad. (singular noun)
2. The buffaloes in the field belong to Encik Salleh. (plural noun)

1. Satellite 110 circled around the earth ten times.
2. The sun rises in the east.

1. Yesterday afternoon, the fire broke out at the Jaya Shopping Complex.
2. The Red Sea is the saltiest ocean in the world. 

Tigers are wild animals.

(Meaning: all tigers)

The tigers are fed twice a day.

(Specific tigers)

Brightly coloured flowers attract butterflies.

(Meaning: all flowers with bright colours attract butterflies)

The flowers in the vase are not real.

(Specific flowers)