The United States' presidential election is only a few months away, but Republican candidate Donald Trump does not seem too keen to work on improving his controversial image.

In the past week alone, he has been involved in a high-profile dispute with the parents of a fallen Muslim soldier, refused to back candidates from his own party and kicked a crying baby out of his rally in Virginia.

Here is a look at groups of people he has offended while running for president.

1. Women

After the first GOP debate in August last year (2015), Mr Trump called the host, Fox News journalist Megyn Kelly, a "bimbo" in a tweet.

During the debate, she confronted him about his rap sheet of derogatory remarks made regarding women.

"You've called women you don't like 'fat pigs,' 'dogs,' 'slobs' and 'disgusting animals'," she said, and asked if he believes he has the "temperament" to be president.

In a subsequent interview with CNN, he said: "You could see there was blood coming out of her eyes. Blood coming out of her wherever."

He explained later that he was referring to her nose.

The feud between them lasted until May this year, where in a sit-down, Mr Trump apologised for calling the journalist a bimbo and said: "Over your life, Megyn, you've been called a lot worse than that, right?"

He previously insulted his early rival in the presidential campaign, Ms Carly Fiorina, in an interview with the Rolling Stone.

"Look at that face! Would anyone vote for that? Can you imagine that, the face of our next president."

2. Hispanics/Latinos

During Mr Trump's presidential campaign announcement, he made a bold statement while expressing his views on immigration.

"When Mexico sends its people, they're not sending their best. They're not sending you. They're not sending you. They're sending people that have lots of problems, and they're bringing those problems with us. They're bringing drugs. They're bringing crime. They're rapists. And some, I assume, are good people."

According to the Business Insider, the statement led major companies to end their business relationships with him.

Several eminent Latino personalities also denounced him, including actress America Ferrera and singer Ricky Martin.

The same speech also saw Mr Trump announce: "I would build a great wall, and nobody builds walls better than me, believe me, and I'll build them very inexpensively. I will build a great, great wall on our southern border. And I will have Mexico pay for that wall."

3. Muslims

In December last year, Mr Trump called for a temporary ban of all Muslims from entering the United States.

This drastic proposal, which the Obama administration condemned, came in the wake of the San Bernadino attack, where a couple who expressed allegiance towards the Islamic State in Iraq and Syria (ISIS) killed 14 people.

He pushed for the ban once more after the deadly Orlando nightclub shooting in June this year. The shooter also pledged allegiance to ISIS.

Most recently, Mr Trump responded to a speech given by Mr Khizr Khan, the father of a dead Muslim American soldier, at the Democratic National Convention by implying that Mr Khan's wife did not speak because she was not permitted to.

"If you look at his wife, she was standing there. She had nothing to say... Maybe she wasn't allowed to have anything to say. You tell me," he said.

This response was met with backlash from not only the public and political figures on the opposing side, but GOP politicians as well.

4. Veterans

Mr Trump's criticism of the Khans, a Gold Star family, received adverse reactions from veterans and veteran groups as well.

In January, Mr Trump boycotted a Republican debate during his month-long feud with Megyn Kelly, and held a fund-raiser for veterans instead.

He claimed to have raised US$6 million (S$8.06 million) for veteran groups, and given US$1 million himself. However, the Washington Post began inquiring about the money, after which Mr Trump called for a press conference to explain.

The publication found that the figures were inaccurate, and that Mr Trump had not made the US$1 million contribution. It was revealed that he began writing cheques only in May after the publication of the Washington Post article.

On Tuesday (Aug 2), Mr Trump kick-started his Virginia rally by informing the crowd of the Purple Heart he generously received from a war veteran, and said: "I always wanted to get the Purple Heart. This was much easier."

However, the veteran told NBC news before the rally that it was actually a replica of his Purple Heart.

A Purple Heart is awarded to military members who are wounded or killed while serving. Mr Trump's comments drew contempt from veteran organisations and people alike.

American politician and veteran, Ms Tammy Duckworth, tweeted a picture of her wounded self receiving a Purple Heart in a hospital bed, with the caption: "This is how one usually looks when you are awarded the Purple Heart. Nothing easy about it."

Sources: CNN, The Washington Post, The New York Times, the Huffington Post, Business Insider, The Guardian, The Telegraph