A woman who plotted to kill her then-husband has been sentenced to five months in jail.

Administrative assistant Amanda Yeo Pei Min, 27, had conspired with her 25-year-old boyfriend - delivery assistant Leong Wei Guo - to sabotage her spouse's car so that he would be killed in a traffic accident.

Yesterday, Deputy Public Prosecutor Houston Johannus told District Judge Chay Yuen Fatt that Yeo had been "fuelled by malice and rage" towards her then-husband - Mr Walter Ting, 28 - who worked as a private-hire car driver.

In seeking a five-month jail term for Yeo, the DPP stressed that she was the mastermind of the plot. He also sought a four-month jail term for Leong, saying he had committed the offence due to a "foolish sense of bravado".

Judge Chay agreed with the DPP.

Leong and Yeo pleaded guilty on Feb 20 to working together and agreeing to cause grievous hurt to Mr Ting by performing a rash act.

The Straits Times understands that they are no longer together. Yeo is also divorced from Mr Ting.

Yeo and Mr Ting married in 2011, and they have two children.

But she later had an affair with Leong, which Mr Ting learnt about in June 2017.

"Walter wanted to divorce Amanda and they quarrelled frequently. Enraged by the acrimonious quarrels, she decided to kill Walter. She conspired with Leong to sabotage Walter's car so that he would get into an accident and die," DPP Johannus had said.

On Jan 6, 2018, Yeo told Leong to puncture Mr Ting's car tyres with some nails. In the wee hours of the next day, Leong went to a multi-storey carpark near Mr Ting's flat in Yung Kuang Road, in Jurong.

With Yeo's help, he found the car and used a pair of pliers to insert a nail into each of its left tyres.

Yeo later told Leong to loosen the wheel bolts on Mr Ting's car, which would be parked near his parents' flat, and cut the brake wires. Early on Jan 11, 2018, Leong went to a multi-storey carpark in Depot Road where Mr Ting's parents live.

He used a wire cutter to cut the anti-braking system wire behind the front right tyre and sent Yeo a picture of the damage.

Leong was later spotted walking around suspiciously with a jacket draped over his head and the police were alerted. Officers arrived soon after and arrested him.